#include<bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define all(x) x.begin(),x.end()
#define pii pair<int,int>
#define pb push_back
#define sz(x) (int)(x.size())
#define chmin(x,y) x=min(x,y)
#define chmax(x,y) x=max(x,y)
#define vi vector<int>
#define vp vector<pii>
#define vvi vector<vi>
#define ykh mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count())
#define __lg(x) 63-__builtin_clzll(x)
#define pow2(x) (1LL<<x)
void __print(int x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifdef local
void setio(){freopen("/Users/iantsai/Library/Mobile Documents/com~apple~CloudDocs/cpp/Empty.md","r",stdin);}
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
void setio(){}
#define debug(x...)
#endif
void setIO(string s) {
freopen((s + ".in").c_str(), "r", stdin);
freopen((s + ".out").c_str(), "w", stdout);
}
struct line{
int a,b;
int operator()(const int x)const{
return a*x+b;
}
};
bool check(line l1,line l2,line l3){
return (l3.b-l2.b)*(l1.a-l2.a)<=(l2.b-l1.b)*(l2.a-l3.a);
}
const int mxn=3e5+5;
struct Palindromic_Tree{
int next[mxn][26];//
int fail[mxn];//跟kmp一樣,存次長以該節點為結尾的回文
int cnt[mxn];//存一個回文有幾個
int num[mxn];//存該節點最長回文的數量
int len[mxn];//存該節點最長回文的長度
int s[mxn];//存字元
int last;//上一個插入的節點
int n;//字串位置指針
int p;//節點指針
int newnode(int l){
for(int i=0;i<26;i++){
next[p][i]=0;
}
cnt[p]=0;
num[p]=0;
len[p]=l;
return p++;
}
void init(){
p=0;
newnode(0);//偶數長度
newnode(-1);//奇數長度
last=0;
n=0;
s[0]=-1;
fail[0]=1;
}
int get_fail(int x){
while(s[n-1-len[x]]!=s[n]){
x=fail[x];
}
return x;
}
void add(int c){
c-='a';
s[++n]=c;
int cur=get_fail(last);
if(!next[cur][c]){
int now=newnode(len[cur]+2);
fail[now]=next[get_fail(fail[cur])][c];//now的次長=last的次長+c,所以要找兩次fail(last->cur->get_fail(cur))
next[cur][c]=now;
num[now]=num[fail[now]]+1;
}
last=next[cur][c];
cnt[last]++;
}
void count(){
for(int i=p-1;i>=0;i--){
cnt[fail[i]]+=cnt[i];
}
}
}tree;
signed main(){
setio();
ios::sync_with_stdio(0);
cin.tie(0);cout.tie(0);
string s;
cin>>s;
tree.init();
for(auto c:s){
tree.add(c);
}
tree.count();
long long ans=0;
for(int i=1;i<tree.p;i++){
debug(tree.len[i],tree.cnt[i]);
chmax(ans,(long long)tree.cnt[i]*tree.len[i]);
}
cout<<ans<<'\n';
}
/*
input:
*/
Compilation message
palindrome.cpp: In function 'void setIO(std::string)':
palindrome.cpp:41:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
41 | freopen((s + ".in").c_str(), "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
palindrome.cpp:42:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
42 | freopen((s + ".out").c_str(), "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
6492 KB |
Output is correct |
2 |
Correct |
1 ms |
6620 KB |
Output is correct |
3 |
Correct |
1 ms |
6492 KB |
Output is correct |
4 |
Correct |
1 ms |
6492 KB |
Output is correct |
5 |
Correct |
1 ms |
6492 KB |
Output is correct |
6 |
Correct |
1 ms |
6492 KB |
Output is correct |
7 |
Correct |
1 ms |
6492 KB |
Output is correct |
8 |
Correct |
1 ms |
6488 KB |
Output is correct |
9 |
Correct |
1 ms |
6488 KB |
Output is correct |
10 |
Correct |
1 ms |
6492 KB |
Output is correct |
11 |
Correct |
1 ms |
6492 KB |
Output is correct |
12 |
Correct |
1 ms |
6492 KB |
Output is correct |
13 |
Correct |
1 ms |
6492 KB |
Output is correct |
14 |
Correct |
1 ms |
6492 KB |
Output is correct |
15 |
Correct |
1 ms |
6492 KB |
Output is correct |
16 |
Correct |
1 ms |
6492 KB |
Output is correct |
17 |
Correct |
1 ms |
6492 KB |
Output is correct |
18 |
Correct |
1 ms |
6492 KB |
Output is correct |
19 |
Correct |
1 ms |
6492 KB |
Output is correct |
20 |
Correct |
1 ms |
6492 KB |
Output is correct |
21 |
Correct |
1 ms |
6492 KB |
Output is correct |
22 |
Correct |
1 ms |
6492 KB |
Output is correct |
23 |
Correct |
1 ms |
6492 KB |
Output is correct |
24 |
Correct |
1 ms |
6492 KB |
Output is correct |
25 |
Correct |
1 ms |
6492 KB |
Output is correct |
26 |
Correct |
1 ms |
6492 KB |
Output is correct |
27 |
Correct |
1 ms |
6492 KB |
Output is correct |
28 |
Correct |
2 ms |
6492 KB |
Output is correct |
29 |
Correct |
1 ms |
6488 KB |
Output is correct |
30 |
Correct |
2 ms |
6492 KB |
Output is correct |
31 |
Correct |
1 ms |
6492 KB |
Output is correct |
32 |
Correct |
1 ms |
6492 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
6488 KB |
Output is correct |
2 |
Correct |
1 ms |
6492 KB |
Output is correct |
3 |
Correct |
1 ms |
6488 KB |
Output is correct |
4 |
Correct |
1 ms |
6488 KB |
Output is correct |
5 |
Correct |
1 ms |
6492 KB |
Output is correct |
6 |
Correct |
1 ms |
6492 KB |
Output is correct |
7 |
Correct |
1 ms |
6492 KB |
Output is correct |
8 |
Correct |
1 ms |
6488 KB |
Output is correct |
9 |
Correct |
1 ms |
6488 KB |
Output is correct |
10 |
Correct |
1 ms |
6740 KB |
Output is correct |
11 |
Correct |
1 ms |
6492 KB |
Output is correct |
12 |
Correct |
1 ms |
6492 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
8796 KB |
Output is correct |
2 |
Correct |
1 ms |
8796 KB |
Output is correct |
3 |
Correct |
1 ms |
8796 KB |
Output is correct |
4 |
Correct |
1 ms |
8796 KB |
Output is correct |
5 |
Correct |
2 ms |
8796 KB |
Output is correct |
6 |
Correct |
2 ms |
8692 KB |
Output is correct |
7 |
Correct |
1 ms |
8792 KB |
Output is correct |
8 |
Correct |
1 ms |
6492 KB |
Output is correct |
9 |
Correct |
1 ms |
6492 KB |
Output is correct |
10 |
Correct |
1 ms |
8796 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
5 ms |
17500 KB |
Output is correct |
2 |
Correct |
5 ms |
17580 KB |
Output is correct |
3 |
Correct |
5 ms |
17500 KB |
Output is correct |
4 |
Correct |
5 ms |
17500 KB |
Output is correct |
5 |
Correct |
4 ms |
17752 KB |
Output is correct |
6 |
Correct |
4 ms |
15452 KB |
Output is correct |
7 |
Correct |
4 ms |
17500 KB |
Output is correct |
8 |
Correct |
2 ms |
7260 KB |
Output is correct |
9 |
Correct |
3 ms |
11432 KB |
Output is correct |
10 |
Correct |
4 ms |
17628 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
15 ms |
37092 KB |
Output is correct |
2 |
Correct |
13 ms |
37272 KB |
Output is correct |
3 |
Correct |
12 ms |
37092 KB |
Output is correct |
4 |
Correct |
12 ms |
37088 KB |
Output is correct |
5 |
Correct |
12 ms |
37092 KB |
Output is correct |
6 |
Correct |
11 ms |
37088 KB |
Output is correct |
7 |
Correct |
11 ms |
35040 KB |
Output is correct |
8 |
Correct |
5 ms |
8164 KB |
Output is correct |
9 |
Correct |
5 ms |
8164 KB |
Output is correct |
10 |
Correct |
11 ms |
35044 KB |
Output is correct |
11 |
Correct |
11 ms |
37184 KB |
Output is correct |
12 |
Correct |
6 ms |
12260 KB |
Output is correct |